This invention relates to cleaner/degreaser compositions and, more particularly, to such compositions comprising a novel surfactant combination which provide enhanced performance characteristics.
Heretofore, cleaners and degreasers containing nonylphenol ethoxylate surfactants have been known and used. However, environmental concerns have been raised concerning the use of such surfactants. Additionally, concerns have been expressed concerning the use of ethylenediamine tetraacetic acid chelants in such cleaners and degreasers. Replacement of nonylphenol ethoxylate surfactants with linear alcohol ethoxylates has been considered, but such substitutions in cleaners and degreasers with these ingredients has caused the performance thereof to suffer.
There is a need therefore for cleaner/degreaser compositions which contain no alcohol, alkylphenol ethoxylate or glycol ether solvent but which exhibits performance characteristics equal to or exceeding the performance of their nonylphenol ethoxylate counterparts.
Among the several objects of the invention may be noted the provision of cleaner or degreaser compositions containing no alcohol, alkylphenol ethoxylate or glycol ether solvent; the provision of such compositions which provide enhanced performance characteristics as compared to compositions containing alkylphenol ethoxylate surfactants; and the provision of such compositions which contain a novel surfactant combination together with an amphoteric surfactant or a coupler or both. Other objects and features will be in part apparent and in part pointed out hereinafter.
Briefly, the present invention is directed to a cleaner or degreaser composition comprising a surfactant combination consisting of (a) a water soluble ethoxylate selected from the group consisting of at least one linear primary or branched secondary alcohol of C9 to C15 chain length and 6 to 13 ethylene oxide groups/mole of alcohol; (b) a water insoluble ethoxylate selected from the group consisting of at least one linear primary or branched secondary alcohol of C9 to C15 chain length and 2.5 to 5 ethylene oxide groupsimoie of alcohol; and (c) a component selected from the group consisting of amphoteric surfactants, couplers and mixtures thereof; the composition containing no alcohol, alkylphenol ethoxylate or glycol ether solvent. It has been found that the use of this particular surfactant combination improves the performance of such cleaner or degreaser compositions so that they are equal to or exceed the performance of counterpart cleaners and degreasers containing nonylphenol ethoxylate surfactants.
In carrying out the invention, the first component of the surfactant combination of the invention is a water soluble ethoxylate selected from the group consisting of at least one linear primary or branched secondary alcohol of C9 to C15 chain length and 6 to 13 ethylene oxide groups/mole of alcohol. Among the specific water soluble ethoxylates which may be used in the practice of the invention may be mentioned Neodol 1-9 (a soluble C11 linear alcohol oxide), Neodol 91-6 (a soluble C9-11 linear alcohol with 6 moles of ethylene oxide), Neodol 91-8 (a soluble C12-13 linear alcohol with 8 moles of ethylene oxide), Neodol 23-6.5 (a soluble C12-13 linear alcohol with 6.5 moles of ethylene oxide), Neodol 25-9 (a soluble C12-15 linear alcohol with 9 moles of ethylene oxide) and Neodol 45-13 (a soluble C14-15 linear alcohol with 13 moles of ethylene oxide). These Neodol surfactants are all available from Shell Chemical Company. Other water soluble ethoxylates useful in the present invention include Tergitol 15-S-9 (a soluble secondary alcohol ethoxylate having the formula C12-14H25-29O(CH2CH2O)xH wherein x is 9 moles of ethylene oxide) and Tergitol 15-S-12 (a soluble secondary alcohol ethoxylate of the above formula wherein x is 12 moles of ethylene oxide). These Tergitol products are available from Union Carbide. Also useful is Surfonic L24-9 (a water soluble ethoxylate from Huntsman of linear, primary alcohol of C12-14 chain length and 9 moles of ethylene oxide).
It will be understood that other water soluble ethoxylates consisting of at least one linear primary or branched secondary alcohol of C9 to C15 chain length and 6 to 13 ethylene oxide groups/mole of alcohol known to those skilled in the art may also be used in the practice of the invention.
The second component of the cleaner or degreaser compositions of the invention is a water insoluble ethoxylate selected from the group consisting of at least one linear primary or branched secondary alcohol of C9 to C15 chain length and 2.5 to 5 ethylene oxide groups/mole of alcohol. Exemplary water insoluble ethoxylates of this type for use in the present invention include Neodol 1-3 (an insoluble C11 linear alcohol with 3 moles of ethylene oxide), Neodol 91-2.5 (an insoluble C9-11linear alcohol with 2.5 moles of ethylene oxide), Neodol 1-5 (an insoluble C11 linear alcohol with 5 moles of ethylene oxide), Neodol 23-3 (an insoluble C12-13 linear alcohol with 3 moles of ethylene oxide), Neodol 25-3 (an insoluble C12-15linear alcohol with 3 moles of ethylene oxide), Neodol 45-2.5 (an insoluble C14-15 linear alcohol with 2.5 moles of ethylene oxide), and Tergitol 15-S-3 (an insoluble secondary alcohol ethoxylate with 3 moles of ethylene oxide).
It will be understood that other water insoluble ethoxylates consisting of at least one linear primary or branched secondary alcohol of C9 to C15 chain length and 2.5 to 5 ethylene oxide groups/mole of alcohol known to those skilled in the art may also be used in the practice of the invention.
The third component of the cleaner or degreaser compositions of the invention is an amphoteric surfactant, a coupler or a mixture of an amphoteric surfactant and a coupler. Among the amphoteric surfactants which may be employed are isodecyloxypropylimino dipropionic acid monosodium salt (sold under the trade designation xe2x80x9cAlkali Surfactant NMxe2x80x9d by Tomah Products, Inc.), sodium iminodipropionate (sold under the trade designation xe2x80x9cAmphoteric 400xe2x80x9d by Tomah Products, Inc.), an alkylether hydoxypropyl sultaine (marketed under the trade designation xe2x80x9cMirataine ASCxe2x80x9d by Rhodia), sodium 2-ethylhexyl sulfate and sodium diisopropylnaphthalenesulfonate (marketed under the trade designation xe2x80x9cNaxan DSLxe2x80x9d by Rutgers). Other amphoteric surfactants which may be utilized include cocamidopropyl betaine, sodium palmityloamphopropionate, disodium N-lauryl-iminodipropionate and sodium coco imidazoline amphoglycinate. The use of xe2x80x9cAlkali Surfactant NMxe2x80x9d mentioned above is preferred.
Various couplers known to the art may also be used in the practice of the invention including isononanoic acid, sodium cumene sulfonate, sodium xylene sulfonate, sodium benzene sulfonate, sodium toluene sulfonate, potassium ethylbenzene sulfonate, sodium octane-1-sulfonate, ammonium xylene sulfonate, sodium-2-ethylhexonoate, sodium pelargonate and disodium capryloiminodipropionate. Other couplers known to those skilled in the art may also be employed. Isononanoic acid is the preferred coupler for use in the present invention.
While the compositions of the invention may be prepared using either an amphoteric surfactant or a coupler as the third component, it is preferred to use a mixture of an amphoteric surfactant and a coupler. More specifically, the use of a mixture of xe2x80x9cAlkali Surfactant NMxe2x80x9d as the amphoteric surfactant and isononanoic acid as the coupler is preferred.
The compositions of the invention may contain various proportions of the three components. In general, it is preferred that the weight percent of the water soluble ethoxylate in the composition be less than twice the weight percent of the water insoluble ethoxylate. Further, in a preferred embodiment of the invention, the composition contains three parts by weight of the water soluble ethoxylate component to two parts by weight of the water insoluble ethoxylate component.
It is important that the compositions of the invention contain substantially no alcohol, alkylphenol ethoxylate (e.g. nonylphenol ethoxylate) or glycol ether solvent. As shown by the working examples set forth hereinafter, the performance characteristics of the cleaner or degreaser compositions of the invention are enhanced by the novel surfactant combination utilized in the practice of the invention. This enhancement is achieved without raising environmental concerns.